/* Copyright (c) 2012 Nordic Semiconductor. All Rights Reserved.
 *
 * The information contained herein is confidential property of Nordic
 * Semiconductor ASA.Terms and conditions of usage are described in detail
 * in NORDIC SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
 *
 * Licensees are granted free, non-transferable use of the information. NO
 * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
 * the file.
 *
 * $$
 */

/** @file
 *
 * @defgroup ble_sdk_app_hids_keyboard_main main.c
 * @{
 * @ingroup ble_sdk_app_hids_keyboard
 * @brief HID Keyboard Sample Application main file.
 *
 * This file contains is the source code for a sample application using the HID, Battery and Device
 * Information Services for implementing a simple keyboard functionality.
 * Pressing Button 0 will send text 'hello' to the connected peer. On receiving output report,
 * it toggles the state of LED 2 on the mother board based on whether or not Caps Lock is on.
 * This application uses the @ref app_scheduler.
 *
 * Also it would accept pairing requests from any peer device. This implementation of the
 * application will not know whether a connected master is a known device or not.
 */

#include <stdint.h>
#include <string.h>
#include "nordic_common.h"
#include "nrf.h"
#include "nrf_assert.h"
#include "nrf_error.h"
#include "nrf_gpio.h"
#include "nrf51_bitfields.h"
#include "ble.h"
#include "ble_srv_common.h"
#include "ble_advdata.h"
#include "ble_hids.h"
#include "ble_bas.h"
#include "ble_dis.h"
#include "ble_conn_params.h"
#include "ble_nrf6310_pins.h"
#include "ble_sensorsim.h"
#include "app_scheduler.h"
#include "app_scheduler_cfg.h"
#include "ble_stack_handler.h"
#include "app_timer.h"


#define KEY_PRESS_BUTTON_PIN_NO          NRF6310_BUTTON_0                   /**< Button used for sending keyboard text. */
#define CAPS_ON_LED_PIN_NO               NRF6310_LED_2                      /**< Pin for indicating that CAPS LOCK is on. */

#define DEVICE_NAME                      "Keyboard_0.1"                     /**< Name of device. Will be included in the advertising data. */
#define MANUFACTURER_NAME                "NordicSemiconductor"              /**< Manufacturer. Will be passed to Device Information Service. */

#define BATTERY_LEVEL_MEAS_INTERVAL      2000                               /**< Battery level measurement interval (milliseconds). */
#define MIN_BATTERY_LEVEL                81                                 /**< Minimum simulated battery level. */
#define MAX_BATTERY_LEVEL                100                                /**< Maximum simulated battery level. */
#define BATTERY_LEVEL_INCREMENT          1                                  /**< Increment between each simulated battery level measurement. */

#define PNP_ID_VENDOR_ID_SOURCE          0x02                               /**< Vendor ID Source. */
#define PNP_ID_VENDOR_ID                 0x1915                             /**< Vendor ID. */
#define PNP_ID_PRODUCT_ID                0xEEEE                             /**< Product ID. */
#define PNP_ID_PRODUCT_VERSION           0x0001                             /**< Product Version. */

#define APP_ADV_INTERVAL                 64                                 /**< The advertising interval (in units of 0.625 ms. This value corresponds to 40 ms). */
#define APP_ADV_TIMEOUT_IN_SECONDS       180                                /**< The advertising timeout (in units of seconds). */

#define MIN_CONN_INTERVAL                6                                  /**< Minimum connection interval (7.5 ms) */
#define MAX_CONN_INTERVAL                24                                 /**< Maximum connection interval (30 ms). */
#define SLAVE_LATENCY                    6                                  /**< Slave latency. */
#define CONN_SUP_TIMEOUT                 (3 * 100)                          /**< Connection supervisory timeout (300 ms). */
#define FIRST_CONN_PARAMS_UPDATE_DELAY   (5 * 1000)                         /**< Time from initiating event (connect or start of notification) to first time ble_gap_conn_param_update is called (5 seconds). */
#define NEXT_CONN_PARAMS_UPDATE_DELAY    (30 * 1000)                        /**< Time between each call to ble_gap_conn_param_update after the first (30 seconds). */
#define MAX_CONN_PARAMS_UPDATE_COUNT     3                                  /**< Number of attempts before giving up the connection parameter negotiation. */

#define SEC_PARAM_TIMEOUT                60                                 /**< Timeout for Pairing Request or Security Request (in seconds). */
#define SEC_PARAM_BOND                   1                                  /**< Perform bonding. */
#define SEC_PARAM_MITM                   0                                  /**< Man In The Middle protection not required. */
#define SEC_PARAM_IO_CAPABILITIES        BLE_GAP_IO_CAPS_NONE               /**< No I/O capabilities. */
#define SEC_PARAM_OOB                    0                                  /**< Out Of Band data not available. */
#define SEC_PARAM_MIN_KEY_SIZE           7                                  /**< Minimum encryption key size. */
#define SEC_PARAM_MAX_KEY_SIZE           16                                 /**< Maximum encryption key size. */

#define OUTPUT_REPORT_INDEX              0                                  /**< Index of Output Report. */
#define OUTPUT_REPORT_MAX_LEN            1                                  /**< Maximum length of Output Report. */
#define INPUT_REPORT_KEYS_INDEX          0                                  /**< Index of Input Report. */
#define OUTPUT_REPORT_BIT_MASK_CAPS_LOCK 0x02                               /**< CAPS LOCK bit in Output Report (based on 'LED Page (0x08)' of the Universal Serial Bus HID Usage Tables). */

#define BASE_USB_HID_SPEC_VERSION        0x0101                             /**< Version number of base USB HID Specification implemented by this application. */

static ble_hids_t                        s_hids;                            /**< Structure used to identify the HID service. */
static ble_bas_t                         s_bas;                             /**< Structure used to identify the battery service. */
static ble_gap_sec_params_t              s_sec_params;                      /**< Security requirements for this application. */
static bool                              s_in_boot_mode = false;            /**< Current protocol mode. */

static ble_sensorsim_cfg_t               s_battery_sim_cfg;                 /**< Battery Level sensor simulator configuration. */
static ble_sensorsim_state_t             s_battery_sim_state;               /**< Battery Level sensor simulator state. */

static uint8_t s_sample_key_press_pattern[] =                               /**< Key pattern to be sent when the key press button has been pushed. */
{
    0x00, /* Modifier status byte */
    0x00, /* Reserved 0x00 */
    0x0b, /* Key h */
    0x08, /* Key e */
    0x0f, /* Key l */
    0x0f, /* Key l */
    0x12, /* Key o */
    0x28  /* Key Return */
};

static uint8_t s_caps_on_key_pattern[] =                                    /**< Key pattern to be sent when the output report has been written with the CAPS LOCK bit set. */
{
    0x00, /* Modifier status byte */
    0x00, /* Reserved 0x00 */
    0x06, /* Key C */
    0x04, /* Key a */
    0x13, /* Key p */
    0x16, /* Key s */
    0x12, /* Key o */
    0x11  /* Key n */
};

static uint8_t s_caps_off_key_pattern[] =                                   /**< Key pattern to be sent when the output report has been written with the CAPS LOCK bit cleared. */
{
    0x00, /* Modifier status byte */
    0x00, /* Reserved 0x00 */
    0x06, /* Key C */
    0x04, /* Key a */
    0x13, /* Key p */
    0x16, /* Key s */
    0x12, /* Key o */
    0x09  /* Key f */
};

#define INPUT_REPORT_KEYS_MAX_LEN           \
    MAX(MAX(sizeof(s_caps_off_key_pattern), \
            sizeof(s_caps_on_key_pattern)), \
        sizeof(s_sample_key_press_pattern))                                 /**< Maximum length of the Input Report characteristic. */

static uint8_t s_sample_key_release_pattern[INPUT_REPORT_KEYS_MAX_LEN] =    /**< Key pattern to be sent to simulate releasing keys. */
{ 
    0x00
};


static void on_hids_evt(ble_hids_t * p_hids, ble_hids_evt_t * p_evt);


/**@brief Assert macro callback function.
 *
 * @details This function will be called if the ASSERT macro fails.
 *
 * @param[in]   line_num   Line number of the failing ASSERT call.
 * @param[in]   file_name  File name of the failing ASSERT call.
 */
void assert_nrf_callback(uint16_t line_num, const uint8_t * file_name)
{
    // Copying parameters to static variables because parameters are not accessible in debugger
    static volatile uint8_t  s_file_name[128];      
    static volatile uint16_t s_line_num;

    strcpy((char *)s_file_name, (const char *)file_name);
    s_line_num = line_num;
    UNUSED_VARIABLE(s_file_name);
    UNUSED_VARIABLE(s_line_num);
    
    nrf_gpio_pin_set(ASSERT_LED_PIN_NO);

    for (;;)
    {
        // Loop forever. On assert, the system can only recover on reset
    }
}


/**@brief Service error handler.
 *
 * @details A pointer to this function will be passed to each service which may need to inform the
 *          application about an error.
 *
 * @param[in]   nrf_error   Error code containing information about what went wrong.
 */
static void service_error_handler(uint32_t nrf_error)
{
    ASSERT(false);
}


/**@brief Perform battery measurement, and update Battery Level characteristic in Battery Service.
 */
static void battery_level_update(void)
{
    uint32_t err_code;
    uint8_t  battery_level;

    battery_level = (uint8_t)ble_sensorsim_measure(&s_battery_sim_state, &s_battery_sim_cfg);

    err_code = ble_bas_battery_level_update(&s_bas, battery_level);
    if (
        (err_code != NRF_SUCCESS) 
        && 
        (err_code != NRF_ERROR_INVALID_STATE) 
        && 
        (err_code != BLE_ERROR_NO_TX_BUFFERS)
        &&
        (err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING)
    )
    {
        ASSERT(false);
    }
}


/**@brief Battery measurement timer timeout handler.
 *
 * @details This function will be called each time the battery level measurement timer expires.
 *
 * @param[in]   timer_id   Id of timer that has expired.
 */
static void battery_level_meas_timeout_handler(app_timer_id_t timer_id)
{
    ASSERT(timer_id == APP_TIMER_BATTERY_LEVEL_MEAS);
    battery_level_update();
}


/**@brief LEDs initialization.
 *
 * @details Initializes all LEDs used by this application.
 */
static void leds_init(void)
{
    GPIO_LED_CONFIG(ADVERTISING_LED_PIN_NO);
    GPIO_LED_CONFIG(CONNECTED_LED_PIN_NO);
    GPIO_LED_CONFIG(ASSERT_LED_PIN_NO);
    GPIO_LED_CONFIG(CAPS_ON_LED_PIN_NO);
}


/**@brief Timer initialization.
 *
 * @details Initializes the timer module.
 */
static void timers_init(void)
{
    uint32_t err_code;

    // Initialize timer module, making it use the scheduler
    err_code = app_timer_init(app_sched_timer_event_schedule);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief GAP initialization.
 *
 * @details This function shall be used to setup all the necessary GAP (Generic Access Profile)
 *          parameters of the device. It also sets the permissions and appearance.
 */
static void gap_params_init(void)
{
    uint32_t                err_code;
    ble_gap_conn_params_t   gap_conn_params;
    ble_gap_conn_sec_mode_t sec_mode;

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&sec_mode);

    err_code = ble_gap_device_name_set(&sec_mode, DEVICE_NAME);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }

    err_code = ble_gap_appearance_set(BLE_APPEARANCE_KEYBOARD_HID_SUBTYPE);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }

    memset(&gap_conn_params, 0, sizeof(gap_conn_params));

    gap_conn_params.min_conn_interval = MIN_CONN_INTERVAL;
    gap_conn_params.max_conn_interval = MAX_CONN_INTERVAL;
    gap_conn_params.slave_latency     = SLAVE_LATENCY;
    gap_conn_params.conn_sup_timeout  = CONN_SUP_TIMEOUT;

    err_code = ble_gap_ppcp_set(&gap_conn_params);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Advertising functionality initialization.
 *
 * @details Encodes the required advertising data and passes it to the stack.
 *          Also builds a structure to be passed to the stack when starting advertising.
 */
static void advertising_init(void)
{
    uint32_t      err_code;
    ble_advdata_t advdata;
    uint8_t       flags = BLE_GAP_DISC_MODE_LIMITED | BLE_GAP_DISC_BR_EDR_NOT_SUPPORTED;

    ble_uuid_t adv_uuids[] = { { BLE_UUID_HUMAN_INTERFACE_DEVICE_SERVICE, BLE_UUID_TYPE_BLE } };

    // Build and set advertising data
    memset(&advdata, 0, sizeof(advdata));

    advdata.name_type               = BLE_ADVDATA_FULL_NAME;
    advdata.include_appearance      = true;
    advdata.flags.size              = sizeof(flags);
    advdata.flags.p_data            = &flags;
    advdata.uuids_complete.uuid_cnt = sizeof(adv_uuids) / sizeof(adv_uuids[0]);
    advdata.uuids_complete.p_uuids  = adv_uuids;

    err_code = ble_advdata_set(&advdata, NULL);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Initialize Device Information Service.
 */
static void dis_init(void)
{
    uint32_t         err_code;
    ble_dis_init_t   dis_init_obj;
    ble_dis_pnp_id_t pnp_id;

    pnp_id.vendor_id_source = PNP_ID_VENDOR_ID_SOURCE;
    pnp_id.vendor_id        = PNP_ID_VENDOR_ID;
    pnp_id.product_id       = PNP_ID_PRODUCT_ID;
    pnp_id.product_version  = PNP_ID_PRODUCT_VERSION;

    memset(&dis_init_obj, 0, sizeof(dis_init_obj));

    ble_srv_ascii_to_utf8(&dis_init_obj.manufact_name_str, MANUFACTURER_NAME);
    dis_init_obj.p_pnp_id = &pnp_id;

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&dis_init_obj.dis_attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&dis_init_obj.dis_attr_md.write_perm);

    err_code = ble_dis_init(&dis_init_obj);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Initialize Battery Service.
 */
static void bas_init(void)
{
    uint32_t       err_code;
    ble_bas_init_t bas_init_obj;

    memset(&bas_init_obj, 0, sizeof(bas_init_obj));

    bas_init_obj.evt_handler          = NULL;
    bas_init_obj.support_notification = true;
    bas_init_obj.p_report_ref         = NULL;
    bas_init_obj.initial_batt_level   = 100;

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&bas_init_obj.battery_level_char_attr_md.cccd_write_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&bas_init_obj.battery_level_char_attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&bas_init_obj.battery_level_char_attr_md.write_perm);

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&bas_init_obj.battery_level_report_read_perm);

    err_code = ble_bas_init(&s_bas, &bas_init_obj);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Initialize HID Service.
 */
static void hids_init(void)
{
    uint32_t                   err_code;
    ble_hids_init_t            hids_init_obj;
    ble_hids_inp_rep_init_t    input_report_array[1];
    ble_hids_inp_rep_init_t  * p_input_report;
    ble_hids_outp_rep_init_t   output_report_array[1];
    ble_hids_outp_rep_init_t * p_output_report;
    uint8_t                    hid_info_flags;

    static uint8_t report_map_data[] =
    {
        0x05, 0x01,                 // Usage Page (Generic Desktop)
        0x09, 0x06,                 // Usage (Keyboard)
        0xA1, 0x01,                 // Collection (Application)
        0x05, 0x07,                 //     Usage Page (Key Codes)
        0x19, 0xe0,                 //     Usage Minimum (224)
        0x29, 0xe7,                 //     Usage Maximum (231)
        0x15, 0x00,                 //     Logical Minimum (0)
        0x25, 0x01,                 //     Logical Maximum (1)
        0x75, 0x01,                 //     Report Size (1)
        0x95, 0x08,                 //     Report Count (8)
        0x81, 0x02,                 //     Input (Data, Variable, Absolute)
    
        0x95, 0x01,                 //     Report Count (1)
        0x75, 0x08,                 //     Report Size (8)
        0x81, 0x01,                 //     Input (Constant) reserved byte(1)
    
        0x95, 0x05,                 //     Report Count (5)
        0x75, 0x01,                 //     Report Size (1)
        0x05, 0x08,                 //     Usage Page (Page# for LEDs)
        0x19, 0x01,                 //     Usage Minimum (1)
        0x29, 0x05,                 //     Usage Maximum (5)
        0x91, 0x02,                 //     Output (Data, Variable, Absolute), Led report
        0x95, 0x01,                 //     Report Count (1)
        0x75, 0x03,                 //     Report Size (3)
        0x91, 0x01,                 //     Output (Data, Variable, Absolute), Led report padding
    
        0x95, 0x06,                 //     Report Count (6)
        0x75, 0x08,                 //     Report Size (8)
        0x15, 0x00,                 //     Logical Minimum (0)
        0x25, 0x65,                 //     Logical Maximum (101)
        0x05, 0x07,                 //     Usage Page (Key codes)
        0x19, 0x00,                 //     Usage Minimum (0)
        0x29, 0x65,                 //     Usage Maximum (101)
        0x81, 0x00,                 //     Input (Data, Array) Key array(6 bytes)
    
        0x09, 0x05,                 //     Usage (Vendor Defined)
        0x15, 0x00,                 //     Logical Minimum (0)
        0x26, 0xFF, 0x00,           //     Logical Maximum (255)
        0x75, 0x08,                 //     Report Count (2)
        0x95, 0x02,                 //     Report Size (8 bit)
        0xB1, 0x02,                 //     Feature (Data, Variable, Absolute)

        0xC0                        // End Collection (Application)    
    };

    // Initialize HID Service
    p_input_report                      = &input_report_array[INPUT_REPORT_KEYS_INDEX];
    p_input_report->writable            = true;
    p_input_report->max_len             = INPUT_REPORT_KEYS_MAX_LEN;
    p_input_report->rep_ref.report_id   = 0;
    p_input_report->rep_ref.report_type = BLE_HIDS_REP_TYPE_INPUT;
    
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&p_input_report->attr_md.cccd_write_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&p_input_report->attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&p_input_report->attr_md.write_perm);

    p_output_report                      = &output_report_array[OUTPUT_REPORT_INDEX];
    p_output_report->max_len             = OUTPUT_REPORT_MAX_LEN;
    p_output_report->rep_ref.report_id   = 0;
    p_output_report->rep_ref.report_type = BLE_HIDS_REP_TYPE_OUTPUT;
    
    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&p_output_report->attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&p_output_report->attr_md.write_perm);

    hid_info_flags = HID_INFO_FLAG_REMOTE_WAKE_MSK | HID_INFO_FLAG_NORMALLY_CONNECTABLE_MSK;

    memset(&hids_init_obj, 0, sizeof(hids_init_obj));

    hids_init_obj.evt_handler                    = on_hids_evt;
    hids_init_obj.error_handler                  = service_error_handler;
    hids_init_obj.is_kb                          = true;
    hids_init_obj.is_mouse                       = false;
    hids_init_obj.inp_rep_count                  = 1;
    hids_init_obj.p_inp_rep_array                = input_report_array;
    hids_init_obj.outp_rep_count                 = 1;
    hids_init_obj.p_outp_rep_array               = output_report_array;
    hids_init_obj.feature_rep_count              = 0;
    hids_init_obj.p_feature_rep_array            = NULL;
    hids_init_obj.rep_map.data_len               = sizeof(report_map_data);
    hids_init_obj.rep_map.p_data                 = report_map_data;
    hids_init_obj.is_boot_kb_inp_rep_writable    = false;
    hids_init_obj.is_boot_mouse_inp_rep_writable = false;
    hids_init_obj.hid_information.bcd_hid        = BASE_USB_HID_SPEC_VERSION;
    hids_init_obj.hid_information.b_country_code = 0;
    hids_init_obj.hid_information.flags          = hid_info_flags;
    hids_init_obj.included_services_count        = 0;
    hids_init_obj.p_included_services_array      = NULL;

    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.rep_map.rep_map_attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&hids_init_obj.rep_map.rep_map_attr_md.write_perm);
    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.hid_information.char_attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&hids_init_obj.hid_information.char_attr_md.write_perm);

    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.hids_boot_kb_inp_rep.cccd_write_perm);
    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.hids_boot_kb_inp_rep.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&hids_init_obj.hids_boot_kb_inp_rep.write_perm);
    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.hids_boot_kb_outp_rep.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.hids_boot_kb_outp_rep.write_perm);

    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.hids_protocol_mode_attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.hids_protocol_mode_attr_md.write_perm);
    BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&hids_init_obj.hids_ctrl_point.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hids_init_obj.hids_ctrl_point.write_perm);

    err_code = ble_hids_init(&s_hids, &hids_init_obj);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Initialize services that will be used by the application.
 */
static void services_init(void)
{
    dis_init();
    bas_init();
    hids_init();
}


/**@brief Initialize the battery sensor simulator.
 */
static void sensor_sim_init(void)
{
    s_battery_sim_cfg.min          = MIN_BATTERY_LEVEL;
    s_battery_sim_cfg.max          = MAX_BATTERY_LEVEL;
    s_battery_sim_cfg.incr         = BATTERY_LEVEL_INCREMENT;
    s_battery_sim_cfg.start_at_max = true;

    ble_sensorsim_init(&s_battery_sim_state, &s_battery_sim_cfg);
}


/**@brief Initialize security parameters.
 */
static void sec_params_init(void)
{
    s_sec_params.timeout      = SEC_PARAM_TIMEOUT;
    s_sec_params.bond         = SEC_PARAM_BOND;
    s_sec_params.mitm         = SEC_PARAM_MITM;
    s_sec_params.io_caps      = SEC_PARAM_IO_CAPABILITIES;
    s_sec_params.oob          = SEC_PARAM_OOB;  
    s_sec_params.min_key_size = SEC_PARAM_MIN_KEY_SIZE;
    s_sec_params.max_key_size = SEC_PARAM_MAX_KEY_SIZE;
}


/**@brief Connection Parameters module error handler.
 *
 * @param[in]   nrf_error   Error code containing information about what went wrong.
 */
static void conn_params_error_handler(uint32_t nrf_error)
{
    ASSERT(false);
}


/**@brief Initialize the Connection Parameters module.
 */
static void conn_params_init(void)
{
    uint32_t               err_code;
    ble_conn_params_init_t cp_init;
    ble_hids_rep_char_t    input_rep_char = s_hids.inp_rep_array[INPUT_REPORT_KEYS_INDEX];
    
    memset(&cp_init, 0, sizeof(cp_init));

    cp_init.p_conn_params                  = NULL;
    cp_init.first_conn_params_update_delay = FIRST_CONN_PARAMS_UPDATE_DELAY;
    cp_init.next_conn_params_update_delay  = NEXT_CONN_PARAMS_UPDATE_DELAY;
    cp_init.max_conn_params_update_count   = MAX_CONN_PARAMS_UPDATE_COUNT;
    cp_init.start_on_notify_cccd_handle    = input_rep_char.char_handles.cccd_handle;
    cp_init.disconnect_on_fail             = false;
    cp_init.evt_handler                    = NULL;
    cp_init.error_handler                  = conn_params_error_handler;
    
    err_code = ble_conn_params_init(&cp_init);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Start timers.
 */
static void timers_start(void)
{
    uint32_t err_code;
    
    err_code = app_timer_start(APP_TIMER_BATTERY_LEVEL_MEAS, 
                               battery_level_meas_timeout_handler, 
                               BATTERY_LEVEL_MEAS_INTERVAL, 
                               APP_TIMER_MODE_REPEATED, 
                               APP_SCHED_QUEUE_LOW_PRI);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Start advertising.
 */
static void advertising_start(void)
{
    uint32_t             err_code;
    ble_gap_adv_params_t adv_params;

    // Start advertising
    memset(&adv_params, 0, sizeof(adv_params));

    adv_params.type        = BLE_GAP_ADV_TYPE_ADV_IND;
    adv_params.p_peer_addr = NULL;
    adv_params.fp          = BLE_GAP_ADV_FP_ANY;
    adv_params.interval    = APP_ADV_INTERVAL;
    adv_params.timeout     = APP_ADV_TIMEOUT_IN_SECONDS;

    err_code = ble_gap_adv_start(&adv_params);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }

    nrf_gpio_pin_set(ADVERTISING_LED_PIN_NO);
}


/**@brief This function will send sample key presses to the peer.
 *
 * @param[in]   key_pattern_len   Pattern length.
 * @param[in]   p_key_pattern     Pattern to be sent.
 */
static void keys_send(uint8_t key_pattern_len, uint8_t * p_key_pattern)
{
    uint32_t err_code;

    if (s_in_boot_mode)
    {
        err_code = ble_hids_boot_kb_inp_rep_send(&s_hids, 
                                                 key_pattern_len, 
                                                 p_key_pattern);
        if (err_code == NRF_SUCCESS)
        {
            err_code = ble_hids_boot_kb_inp_rep_send(&s_hids, 
                                                     key_pattern_len, 
                                                     s_sample_key_release_pattern);
        }
    }
    else
    {
        err_code = ble_hids_inp_rep_send(&s_hids,
                                         INPUT_REPORT_KEYS_INDEX,
                                         key_pattern_len,
                                         p_key_pattern);
        if (err_code == NRF_SUCCESS)
        {
            err_code = ble_hids_inp_rep_send(&s_hids,
                                             INPUT_REPORT_KEYS_INDEX,
                                             key_pattern_len,
                                             s_sample_key_release_pattern);
        }
    }

    if (
        (err_code != NRF_SUCCESS)
        &&
        (err_code != NRF_ERROR_INVALID_STATE)
        &&
        (err_code != BLE_ERROR_NO_TX_BUFFERS)
        &&
        (err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING)
       )
    {
        ASSERT(false);
    }
}


/**@brief HID Report Characteristic Write event handler.
 *
 * @param[in]   p_evt   HID service event.
 */
static void on_hid_rep_char_write(ble_hids_evt_t *p_evt)
{
    if (p_evt->params.char_write.char_id.rep_type == BLE_HIDS_REP_TYPE_OUTPUT)
    {
        uint32_t err_code;
        uint8_t  report_val;
        uint8_t  report_index = p_evt->params.char_write.char_id.rep_index;
        
        if (report_index == OUTPUT_REPORT_INDEX)
        {
            ASSERT(OUTPUT_REPORT_MAX_LEN == 1);

            err_code = ble_hids_outp_rep_get(&s_hids, 
                                             report_index, 
                                             OUTPUT_REPORT_MAX_LEN, 
                                             0,
                                             &report_val);
            if (err_code != NRF_SUCCESS)
            {
                ASSERT(false);
            }

            if ((report_val & OUTPUT_REPORT_BIT_MASK_CAPS_LOCK) != 0)
            {
                // Caps Lock On
                nrf_gpio_pin_set(CAPS_ON_LED_PIN_NO);
                keys_send(sizeof(s_caps_on_key_pattern), s_caps_on_key_pattern);
            }
            else
            {
                // Caps Lock Off
                nrf_gpio_pin_clear(CAPS_ON_LED_PIN_NO);
                keys_send(sizeof(s_caps_off_key_pattern), s_caps_off_key_pattern);
            }
        }
    }
}


/**@brief HID event handler.
 *
 * @details This function will be called for all HID events which are passed to the application.
 *
 * @param[in]   p_hids  HID service stucture.
 * @param[in]   p_evt   Event received from the HID service.
 */
static void on_hids_evt(ble_hids_t * p_hids, ble_hids_evt_t *p_evt)
{
    switch (p_evt->evt_type)
    {
        case BLE_HIDS_EVT_BOOT_MODE_ENTERED:
            s_in_boot_mode = true;
            break;

        case BLE_HIDS_EVT_REPORT_MODE_ENTERED:
            s_in_boot_mode = false;
            break;

        case BLE_HIDS_EVT_REP_CHAR_WRITE:
            on_hid_rep_char_write(p_evt);
            break;

        default:
            break;
    }
}


/**@brief Application's BLE Stack event handler.
 *
 * @param[in]   p_ble_evt   Bluetooth stack event.
*/
static void on_ble_evt(ble_evt_t * p_ble_evt)
{
    uint32_t                         err_code = NRF_SUCCESS;
    static uint16_t                  s_conn_handle = BLE_CONN_HANDLE_INVALID;
    static ble_gap_evt_auth_status_t s_auth_status;
    ble_gap_enc_info_t *             p_enc_info;

    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_CONNECTED:
            nrf_gpio_pin_set(CONNECTED_LED_PIN_NO);
            nrf_gpio_pin_clear(ADVERTISING_LED_PIN_NO);
            s_conn_handle = p_ble_evt->evt.gatts_evt.conn_handle;
            break;

        case BLE_GAP_EVT_DISCONNECTED:
            nrf_gpio_pin_clear(CONNECTED_LED_PIN_NO);
            nrf_gpio_pin_clear(CAPS_ON_LED_PIN_NO);
            s_conn_handle = BLE_CONN_HANDLE_INVALID;
            advertising_start();
            break;

        case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
            err_code = ble_gap_sec_params_reply(s_conn_handle, 
                                                BLE_GAP_SEC_STATUS_SUCCESS,
                                                &s_sec_params);
            break;

        case BLE_GATTS_EVT_SYS_ATTR_MISSING:
            err_code = ble_gatts_sys_attr_set(s_conn_handle, NULL, 0);
            break;

        case BLE_GAP_EVT_AUTH_STATUS:
            s_auth_status = p_ble_evt->evt.gap_evt.params.auth_status;
            break;

        case BLE_GAP_EVT_SEC_INFO_REQUEST:
            p_enc_info = &s_auth_status.periph_keys.enc_info;
            if (p_enc_info->div == p_ble_evt->evt.gap_evt.params.sec_info_request.div)
            {
                err_code = ble_gap_sec_info_reply(s_conn_handle, p_enc_info, NULL);
            }
            else
            {
                // No keys found for this device
                err_code = ble_gap_sec_info_reply(s_conn_handle, NULL, NULL);
            }
            break;

        case BLE_GAP_EVT_TIMEOUT:
            if (p_ble_evt->evt.gap_evt.params.timeout.src == BLE_GAP_TIMEOUT_TYPE_ADVERTISEMENT)
            { 
                nrf_gpio_pin_clear(ADVERTISING_LED_PIN_NO);

                // Go to system-off mode (this function will not return; wakeup will cause a reset)
                err_code = nrf_power_system_off();    
            }
            break;

        default:
            break;
    }

    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Dispatches a BLE stack event to all modules with a BLE stack event handler.
 *
 * @details This function is called from the scheduler in the main loop after a BLE stack
 *          event has been received.
 *
 * @param[in]   p_ev_data   Scheduler event containing a bluetooth event.
 */
static void ble_evt_dispatch(app_sched_event_data_t * p_ev_data)
{
    ble_evt_t * p_ble_evt;
    
    ASSERT(p_ev_data->event_id == APP_SCHED_EVENT_BLE);
    
    p_ble_evt = &p_ev_data->data.ble.ble_evt;

    on_ble_evt(p_ble_evt);
    ble_conn_params_on_ble_evt(p_ble_evt);
    ble_hids_on_ble_evt(&s_hids, p_ble_evt);
    ble_bas_on_ble_evt(&s_bas, p_ble_evt);
}


/**@brief Pass bluetooth stack event to scheduler.
 *
 * @details This function is called from the BLE Stack event interrupt handler after a BLE stack
 *          event has been received.
 *
 * @param[in]   p_ble_evt   Bluetooth stack event.
 */
static void ble_evt_schedule(ble_evt_t * p_ble_evt)
{
    uint32_t               err_code;
    app_sched_event_data_t ev_data;
    
    ev_data.event_id         = APP_SCHED_EVENT_BLE;
    ev_data.data.ble.ble_evt = *p_ble_evt;
    
    err_code = app_sched_event_put(&ev_data, ble_evt_dispatch, APP_SCHED_QUEUE_LOW_PRI);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief BLE stack initialization.
 *
 * @details Initializes the SoftDevice and the BLE event interrupt.
 */
static void ble_stack_init(void)
{
    uint32_t err_code = ble_stack_handler_init(NRF_CLOCK_LFCLKSRC_XTAL_20_PPM, ble_evt_schedule);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Keyboard event handler.
 *
 * @details This function is called from the scheduler in the main loop after a keyboard
 *          event has been received.
 *
 * @param[in]   p_ev_data   Scheduler event containing a keyboard event.
 */
static void keyboard_event_handler(app_sched_event_data_t *p_ev_data)
{
    ASSERT(p_ev_data->event_id == APP_SCHED_EVENT_KEYBOARD);
    
    // Send sample key pattern
    keys_send(sizeof(s_sample_key_press_pattern), s_sample_key_press_pattern);
}


/**@brief Passes a keyboard event to the Scheduler.
 *
 * @details Will be called from the GPIOTE interrupt handler when a push button event has been 
 *          detected.
 */
static void keyboard_event_schedule(void)
{
    uint32_t               err_code;
    app_sched_event_data_t ev_data;
    
    ev_data.event_id = APP_SCHED_EVENT_KEYBOARD;
    
    err_code = app_sched_event_put(&ev_data, keyboard_event_handler, APP_SCHED_QUEUE_LOW_PRI);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief GPIOTE interrupt handler.
 */
void GPIOTE_IRQHandler(void)
{
    if (
        (NRF_GPIOTE->EVENTS_PORT != 0)
        &&
        ((NRF_GPIOTE->INTENSET & GPIOTE_INTENSET_PORT_Msk) != 0)
    )
    {
        NRF_GPIOTE->EVENTS_PORT = 0;
        if (nrf_gpio_pin_read(KEY_PRESS_BUTTON_PIN_NO) == 0)
        {
            keyboard_event_schedule();
        }
    }
}


/**@brief Initialize GPIOTE module for detecting buttons.
 */
static void buttons_init(void)
{
    uint32_t err_code;
    uint32_t per_rdy;

    // Power on GPIOTE module
    err_code = nrf_power_perpower_set(POWER_PERPOWER_GPIOTE_Msk);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }

    do
    {
        err_code = nrf_power_perrdy_get(&per_rdy);
        if (err_code != NRF_SUCCESS)
        {
            ASSERT(false);
        }
    } while ((per_rdy & POWER_PERRDY_GPIOTE_Msk) == 0);

    // Initialize GPIOTE module
    NRF_GPIOTE->INTENCLR = 0xffffffffUL;
    NRF_GPIOTE->INTENSET = GPIOTE_INTENSET_PORT_Msk;

    // Configure Button 0. The button will also wake up the application.
    NRF_GPIO->PIN_CNF[KEY_PRESS_BUTTON_PIN_NO] =
                                          (GPIO_PIN_CNF_DIR_Input     << GPIO_PIN_CNF_DIR_Pos)    |
                                          (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos)  |
                                          (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos)   |
                                          (GPIO_PIN_CNF_DRIVE_S0S1    << GPIO_PIN_CNF_DRIVE_Pos)  |
                                          (GPIO_PIN_CNF_SENSE_Low     << GPIO_PIN_CNF_SENSE_Pos);
                                          
    err_code = nrf_nvic_ClearPendingIRQ(GPIOTE_IRQn);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }

    err_code = nrf_nvic_SetPriority(GPIOTE_IRQn, NRF_APP_PRIORITY_LOW);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }

    err_code = nrf_nvic_EnableIRQ(GPIOTE_IRQn);
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Power manager.
 */
static void power_manage(void)
{
    uint32_t err_code = nrf_wait_for_app_event();
    if (err_code != NRF_SUCCESS)
    {
        ASSERT(false);
    }
}


/**@brief Application main function.
 */
int main(void)
{
    // Initialize
    leds_init();
    ble_stack_init();
    app_sched_init();
    timers_init();
    buttons_init();
    gap_params_init();
    advertising_init();
    services_init();
    sensor_sim_init();
    conn_params_init();
    sec_params_init();
    
    // Start execution
    timers_start();
    advertising_start();
    
    // Enter main loop
    for (;;)
    {
        app_sched_schedule();
        power_manage();
    }
}

/** 
 * @}
 */
